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Model releasesOpenAIIn its training data

OpenAI releases GPT-5.4 with native computer use

Confirmed

Importance: major (4 of 5)

The takeaway

GPT-5.4 (March 5, 2026) unified GPT-5.3-Codex’s coding strengths with general reasoning and built-in computer use, scoring 75% on OSWorld-Verified — above the 72.4% human baseline — with a 1.05M-token context; mini and nano versions followed on March 17.

Researched and written by AI agents (Claude Opus 5.5 in Claude Code). Human editor: Adam Bicz.

Status
Claim

Confirmed

Our reporting
High confidence
Importance
Major (4 of 5)
Last verified
29 September 2026

Your AI and this story

  • GPT-6 AstraIn its training data
  • Claude Opus 5.5In its training data
  • Gemini 4 HydrogenIn its training data
  • Grok 4.7In its training data

It happened before the cutoffs of all four assistants, so it can be in their training data.

Key facts

  • GPT-5.4 Thinking and GPT-5.4 Pro: March 5, 2026 in ChatGPT, API and Codex
  • GPT-5.4 mini (also for free tier) and GPT-5.4 nano (API only): March 17, 2026
  • OSWorld-Verified: 75% vs 47.3% for GPT-5.2 and 72.4% average human
  • OpenAI: 33% fewer factual errors than GPT-5.2
  • API: $2.50 input / $15 output per 1M tokens; cache read $0.25; input doubles to $5 above 272K tokens
  • Context window 1,050,000 tokens; up to 128K output tokens
  • Critics noted mini/nano API prices were about four times higher than GPT-5 equivalents

What happened

OpenAI released GPT-5.4 as a single model combining reasoning, coding and agentic workflows, including native computer use (reading screenshots, clicking, typing, navigating apps), and improved deep research.

Why it matters

First OpenAI mainline model to beat the human baseline on OSWorld-Verified, marking computer-use agents as a mainstream capability.

Sources

5 sources from 5 sites. Numbers match the chips in the text.

5 sources: 3 primary, 1 press, 1 reaction

Primary

  1. Introducing GPT-5.4 (OpenAI)openai.com, official
  2. GPT-5.4 model docs (OpenAI API)developers.openai.com, docs
  3. OpenRouter: GPT-5.4openrouter.ai, docs

Press

  1. Cybersecurity News: OpenAI launches GPT-5.4cybersecuritynews.com, press

Reactions

  1. Wikipedia: GPT-5.4en.wikipedia.org, discussion

Changes

  • Filed

Status

Claim

Confirmed

Our reporting
High confidence
Importance
Major (4 of 5)
Last verified
29 September 2026

Sources at a glance

5 sources: 3 primary, 1 press, 1 reaction

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
29 September 2026
Human review
None recorded for this entry. What the editor does
Version
Last saved 4 October 2026

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The whole topic